<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Flex</title>
    <style>
        .flex{
            display: flex;
            justify-content: center;
            align-items: center;
            height: 100px;
        }
        .flex1{
            background-color: greenyellow;
            
        }
        .flex2{
            background-color: blueviolet;
            
        }
        .flex3{
            background-color: wheat;
            
        }
    </style>
</head>
<body>
    <div class="flex">
        <div class="flex1">flex1</div>
        <div class="flex2">flex2</div>
        <div class="flex3">flex3</div>
    </div>
</body>
</html>